Forget The Basics, Tell Us Your Most Mind-Blowing Math Trick

I am so glad I know the easy hack to figure out a 20% tip.

I'm a writer by trade, and for some reason that means I'm OK at English and just plain bad at math.

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Which means I rely on little math tricks to get me by.

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For example, I tip 20% everywhere just because I know 20% is moving the total's decimal over one number to the left, then doubling it.

For example, a 20% tip on a $63.00 bill is $12.60 ($6.30 x 2 = $12.60).

And if I'm multiplying any number by 5, just half said number and plop a zero at the end.

So 5 x 12 = 60 (half of 12 is 6, then add a 0).

I only have two, so now I want to know if you have a quick math trick you live by that makes life a heck of a lot easier.

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For all the liberal arts majors out there, if you have a practical math tip, float it to us in the comments below and your tip could be used in an upcoming BuzzFeed Community post. Thanks for helping all of the right brains out!

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